function Isacrobatplugininstall () {varFlag =false; //if it's a Firefox browser if(Navigator.plugins &&navigator.plugins.length) { for(x =0; x < navigator.plugins.length; X + +) { if(Navigator.plugins[x].name = ='Adobe Acrobat') Flag=true; } } //The following code is the case of IE browser processing Else if(window. ActiveXObject) { for(x =2; X <Ten; X + +) { Try{Oacro= Eval_r ("new ActiveXObject (' Pdf.pdfctrl."+ x +"');"); if(oacro) {flag=true; } } Catch(e) {flag=false; } } Try{OAcro4=NewActiveXObject ('PDF.PDFCTRL.1'); if(OACRO4) flag=true; } Catch(e) {flag=false; } Try{OAcro7=NewActiveXObject ('ACROPDF.PDF.1'); if(OACRO7) flag=true; } Catch(e) {flag=false; } } if(flag) {alert ("Yes"); return true; } Else{alert ("Sorry, you have not installed the PDF Reader software yet, for the convenience of previewing PDF documents, please select Install! "); Location='Http://ardownload.adobe.com/pub/adobe/reader/win/9.x/9.3/chs/AdbeRdr930_zh_CN.exe'; } returnFlag; } </script>"Button"Value="jiance"onclick="Isacrobatplugininstall ()"/></body>JS to determine if the client has a PDF reader installed